The present invention relates generally to a thermal cycling device and method of performing nucleic acid amplification on a plurality of biological samples positioned in a sample well tray. More particularly, the present invention relates in one aspect to a thermal cycling device and method of real-time detection of a nucleic acid amplification process such as polymerase chain reaction (PCR).
Biological testing has become an important tool in detecting and monitoring diseases. In the biological testing field, thermal cycling is used to amplify nucleic acids by, for example, performing PCR and other reactions. PCR in particular has become a valuable research tool with applications such as cloning, analysis of genetic expression, DNA sequencing, and drug discovery.
Recent developments in the field have spurred growth in the number of tests that are performed. One method for increasing the throughput of such biological testing is to provide real-time detection capability during thermal cycling. Real-time detection increases the efficiency of the biological testing because the characteristics of the samples can be detected while the sample well tray remains positioned in the thermal cycling device, therefore not requiring removal of the sample well tray to a separate area prior to testing of the samples. In typical real-time thermal cycling devices, the sample well tray is removed after detection is completed.
Various aspects of the invention generally relate to a thermal cycling device in which the sample block assembly may be vertically moved so that the sample well tray may be inserted and removed from the thermal cycling device. The thermal cycling device can be a real-time device. During such movement of the sample block assembly and sample well tray, the optical detection system can remain substantially stationary.
According to one aspect, the invention comprises a thermal cycling device. The thermal cycling device includes a sample block assembly, an optical detection system, and a sample well tray holder. The sample well tray holder includes a tray-receiving region configured to hold a sample well tray. The optical detection system is positioned above the sample block assembly. The sample well tray holder is configured to translate the sample well tray into alignment with the sample block assembly. The sample block assembly is adapted for movement between a first position permitting the translation of the sample well tray into alignment with the sample block assembly, and a second position, upward relative to the first position, where the sample block assembly contacts the sample well tray.
In another aspect, the optical detection system is adapted to remain substantially stationary during insertion and removal of the sample well tray from the thermal cycling device. In a further aspect, the thermal cycling device further includes a positioning mechanism configured to translate the sample block between the first and second positions.
In yet another aspect, the invention comprises a method of performing nucleic acid amplification on a plurality of biological samples positioned in a sample well tray in a thermal cycling device. The method includes the step of placing the sample well tray into a sample well tray holder. The method further includes the step of translating the sample well tray holder and sample well tray into the thermal cycling device until the sample well tray is aligned with a sample block assembly positioned beneath the sample well tray. The method further includes the step of translating the sample block assembly from a first position to a second position. In the first position, the sample block assembly permits the sample well tray to translate into alignment with the sample block assembly. In the second position, the sample block assembly is positioned vertically upward relative to the first position to contact the sample well tray.
The method can further comprise the step of thermally cycling the device while simultaneously optically detecting the samples. The method can further comprise translating the sample block assembly from the second position to the first position. Finally, the method can comprise the step of removing the sample well tray holder and sample well tray from the thermal cycling device. In various embodiments, the optical detection system remains substantially stationary throughout the above steps.
In another aspect, the invention comprises a thermal cycling device. The thermal cycling device includes an optical detection system, a sample block, and a sample well tray holder. The sample block is adapted for movement along a first path, toward and away from the optical detection system. The sample well tray holder includes a tray-receiving region. The sample well tray holder is adapted for movement along a second path, toward and away from a position whereat the tray-receiving region is disposed between the optical detection system and the sample block. The optical detection system can be adapted to remain substantially stationary during movement of the sample block and the sample well tray holder along the first and second paths.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.